WAVE TRANSFORMATIONS OVER A SUBMERGED BAR: EXPERIMENTS AND THEORETICAL INTERPRETATIONS

Gianfranco Liberatore, Marco Petti

Abstract

Random wave tests were performed in a flume to investigate wave transformations above a submerged bar built on a horizontal bottom. Wave data were analysed in the frequency and time domains. In the time domain, reference was made both to short (/>0.5/„) and long waves (with /<0.5/p). This allowed in particular investigation of transformations of long waves passing over the bar. Experimental results were interpreted using a second-order analytical model, able to separate first- and second-order components from given (measured) variance spectra. The analytical method proved to be conveniently applicable as long as breaking phenomena are not too intense.